Reitman's family was by his side in Montecito, CA Saturday night, as he passed peacefully in his sleep.

He produced a string of hits, and not just hits but legendary flicks.  Among his other films ... "Meatballs" and "Stripes."

And, in an homage to his dad, Ivan's son, Jason Reitman, directed "Ghostbusters: Afterlife." Ah, but wait, there's more ... "Twins," "Kindergarten Cop," "Dave," "Junior," and "Six Days, Seven Nights."

Oh, did we mention he also produced "Beethoven," "Old School," and "EuroTrip?"

Kumail Nanjiani was to the point, saying, "The number of great movies he made is absurd."

Ivan was born in 1946 in Czechoslovakia. His mom was a survivor of Auschwitz. His family escaped by taking a barge to Vienna. He recounted the experience ... “I remember flashes of scenes. Later they told me about how they gave me a couple of sleeping pills so I wouldn’t make any noise. I was so knocked out that I slept with my eyes open. My parents were afraid I was dead.”

His family said of Ivan's passing ... “Our family is grieving the unexpected loss of a husband, father, and grandfather who taught us to always seek the magic in life,” children Jason Reitman, Catherine Reitman and Caroline Reitman said in a joint statement. “We take comfort that his work as a filmmaker brought laughter and happiness to countless others around the world. While we mourn privately, we hope those who knew him through his films will remember him always.”